Objective: The purpose of this study was to investigate the factors predicting the maintenance of sinus rhythm in patients with paroxysmal atrial fibrillation (PAF) who underwent cryoablation of the pulmonary veins (PVs).Methods: Fifty-one patients (54.6±10.4 years) with paroxysmal AF who underwent the cryoablation of the PVs were to the prospective trial. The clinical risk factors and echocardiographic parameters [left atrial (LA) diameter, left ventricular ejection fraction and dimensions, left atrial spontaneous echo contrast (LASEC), mitral annulus calcification (MAC), left atrial appendage emptying peak flow velocity (LAAV), and PV flow] were assessed before the cryoablation procedure. Patients with PAF who refused to use any medication because of intolerance or presentation of resistant symptoms, despite the use of at least one antiarrhythmic drug were enrolled to the study, patients with LA/LAA thrombus on echocardiographic examination, severe valvular disease, pericardial fluid, and abnormal thyroid function tests as well as systemic disease were excluded from the study. All parameters were tested for their ability to predict the recurrence of AF during a 1-year follow-up period.Results: During the period of follow-up, AF recurred in 16 of 51 patients (31.3%/year). All significant parameters associated with the recurrence of AF were evaluated in multivariate logistic regression analysis. The presence of MAC (p<0.001) as well as LA diameter (p<0.0001), LAAV of <30 cm/s (p<0.0001), PV flow systolic wave velocity (p<0.0001), and LASEC (p<0.0001) were detected as independent predictors of recurrence. In the receiver operating characteristic analysis, LAAV of >30 cm/s had a sensitivity of 85% and a specificity of 95% for predicting success after ablation (AUC=0.813; 95% CI: 0.760.92; p<0.0001).Conclusion: The presence of MAC, increased LA diameter, the existence of LASEC, low LAAV, and low peak PV systolic wave velocity are parameters that can predict the recurrence of AF after cryoablation. (Anatol J Cardiol 2016; 16: 482-8)